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Nanomaterial-based synergistic antibacterial agents are considered as promising tools to combat infections caused by antibiotic-resistant bacteria. Herein, multifunctional mesoporous silica nanoparticle (MSN)-based nanocomposites were fabricated for synergistic photothermal/photodynamic/chemodynamic therapy against methicillin-resistant Staphylococcus aureus (MRSA). MSN loaded with indocyanine green (ICG) as a core, while Prussian blue (PB) nanostructure was decorated on MSN surface via in situ growth method to form a core-shell nanohybrid (MSN-ICG@PB). Upon a near infrared (NIR) laser excitation, MSN-ICG@PB (200⯵gâ¯mL-1) exhibited highly efficient singlet oxygen (1O2) generation and hyperthermia effect (48.7â). In the presence of exogenous H2O2, PB with peroxidase-like activity promoted the generation of toxic hydroxyl radicals (â¢OH) to achieve chemodynamic therapy (CDT). PTT can greatly increase the permeability of bacterial lipid membrane, facilitating the generated 1O2 and â¢OH to kill bacteria more efficiently. Under NIR irradiation and exogenous H2O2, MSN-ICG@PB (200⯵gâ¯mL-1) with good biocompatibility exhibited a synergistic antibacterial effect against MRSA with high bacterial killing efficiency (>98â¯%). Moreover, due to the synergistic bactericidal mechanism, MSN-ICG@PB with satisfactory biosafety makes it a promising antimicrobial agent to fight against MRSA.
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Antibacterianos , Ferrocianuros , Verde de Indocianina , Staphylococcus aureus Resistente a Meticilina , Fotoquimioterapia , Dióxido de Silicio , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Verde de Indocianina/química , Verde de Indocianina/farmacología , Dióxido de Silicio/química , Dióxido de Silicio/farmacología , Ferrocianuros/química , Ferrocianuros/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Porosidad , Pruebas de Sensibilidad Microbiana , Terapia Fototérmica , Nanopartículas/química , Propiedades de Superficie , Tamaño de la Partícula , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/química , Nanocompuestos/química , Rayos Infrarrojos , Humanos , AnimalesRESUMEN
Reactive oxygen species (ROS) play a vital role in wound healing process by fighting against invaded bacteria. However, excess ROS at the wound sites lead to oxidative stress that can trigger deleterious effects, causing cell death, tissue damage and chronic inflammation. Therefore, we fabricated a core-shell structured nanomedicine with antibacterial and antioxidant properties via a facile and green strategy. Specifically, Prussian blue (PB) nanozyme was fabricated and followed by coating a layer of epigallocatechin-3-gallate (EGCG)-derived polymer via polyphenolic condensation reaction and self-assembly process, resulting in PB@EGCG. The introduction of PB core endowed EGCG-based polyphenol nanoparticles with excellent NIR-triggered photothermal properties. Besides, owing to multiple enzyme-mimic activity of PB and potent antioxidant capacity of EGCG-derived polymer, PB@EGCG exhibited a remarkable ROS-scavenging ability, mitigated intracellular ROS level and protected cells from oxidative damage. Under NIR irradiation (808 nm, 1.5 W/cm2), PB@EGCG (50 µg/mL) exerted synergistic EGCG-derived polymer-photothermal antibacterial activity against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). In vivo therapeutic effect was evaluated using a S. aureus-infected rat model indicated PB@EGCG with a prominent bactericidal ability could modulate the inflammatory microenvironment and accelerate wound healing. Overall, this dual-functional nanomedicine provides a promising strategy for efficient antibacterial therapy.
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Antibacterianos , Antioxidantes , Catequina , Catequina/análogos & derivados , Escherichia coli , Ferrocianuros , Nanopartículas , Polímeros , Especies Reactivas de Oxígeno , Staphylococcus aureus , Catequina/química , Catequina/farmacología , Catequina/administración & dosificación , Ferrocianuros/química , Animales , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Ratas , Polímeros/química , Nanopartículas/química , Antioxidantes/farmacología , Antioxidantes/administración & dosificación , Antioxidantes/química , Masculino , Ratas Sprague-Dawley , Humanos , Infecciones Estafilocócicas/tratamiento farmacológico , Ratones , Terapia Fototérmica/métodos , Estrés Oxidativo/efectos de los fármacosRESUMEN
Monitoring radioactivity levels in the environment around nuclear power plants is of great significance to assessing environmental safety and impact. Shidaowan nuclear power plant is currently undergoing commissioning; however, the baseline soil radioactivity is unknown. The naturally occurring radionuclides 238U, 232Th, 226Ra and 40K, and artificial radionuclide (AR) 137Cs in soil samples around the Shidaowan nuclear power plant were measured to establish the baseline levels. Human health hazard indices such as external hazard indices (Hex), Radium equivalent (Raeq), outdoor absorbed dose rate (Dout), annual effective dose (AED) and excess lifetime cancer risk (ELCR) were estimated. The average concentration of 232Th, 40K, 137Cs, 238U and 226Ra were 42.6 ± 15, 581 ± 131, 0.68 ± 0.38, 40.13 ± 9.07 and 40.8 ± 12.8 Bq per kg, respectively. The average Hex, Raeq, Dout, AED and ELCR were 0.40, 146 Bq per kg, 68.8 nGy per h, 0.09 mSv per y and 3.29E-04, respectively. These data showed an acceptable level of risk to residents near the nuclear power plant and that the current radioactivity in the soil may not pose immediate harm to residents living close to the nuclear power plant. The observed lower AED and 40 K and 137Cs concentrations were comparable to other studies, whilst ELCR was higher than the world average of 2.9E-04. The commissioning of the Shidaowan nuclear power plant is potentially safe for the surrounding residents; further continuous monitoring is recommended.
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Radioisótopos de Cesio , Plantas de Energía Nuclear , Radioisótopos de Potasio , Monitoreo de Radiación , Radio (Elemento) , Contaminantes Radiactivos del Suelo , Torio , Contaminantes Radiactivos del Suelo/análisis , Medición de Riesgo/métodos , China , Monitoreo de Radiación/métodos , Humanos , Radioisótopos de Cesio/análisis , Radio (Elemento)/análisis , Torio/análisis , Radioisótopos de Potasio/análisis , Dosis de Radiación , Uranio/análisisRESUMEN
Protein channels on the biofilm conditionally manipulate ion transport via regulating the distribution of charge residues, making analogous processes on artificial membranes a hot spot and challenge. Here, we employ metal-organic frameworks (MOFs) membrane with charge-adjustable subnano-channel to selectively govern ion transport. Various valent ions are binded with crown ethers embedded in the MOF cavity, which act as charged guest to regulate the channels' charge state from the negativity to positivity. Compared with the negatively charged channel, the positive counterpart obviously enhances Li+ /Mg2+ selectivity, which benefit from the reinforcement of the electrostatic repulsion between ions and the channel. Meanwhile, theoretical calculations reveal that Mg2+ transport through the more positively charged channel needed to overcome higher entrance energy barrier than that of Li+ . This work provides a subtle strategy for ion-selective transport upon regulating the charge state of insulating membrane, which paves the way for the application like seawater desalination and lithium extraction from salt lakes.
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Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia seen in clinical settings, which has been associated with substantial rates of mortality and morbidity. However, clinically available drugs have limited efficacy and adverse effects. We aimed to investigate the mechanisms of action of andrographolide (Andr) with respect to AF. We used network pharmacology approaches to investigate the possible therapeutic effect of Andr. To define the role of Andr in AF, HL-1 cells were pro-treated with Andr for 1 h before rapid electronic stimulation (RES) and rabbits were pro-treated for 1 d before rapid atrial pacing (RAP). Apoptosis, myofibril degradation, oxidative stress, and inflammation were determined. RNA sequencing (RNA-seq) was performed to investigate the relevant mechanism. Andr treatment attenuated RAP-induced atrial electrophysiological changes, inflammation, oxidative damage, and apoptosis both in vivo and in vitro. RNA-seq indicated that oxidative phosphorylation played an important role. Transmission electron microscopy and adenosine triphosphate (ATP) content assay respectively validated the morphological and functional changes in mitochondria. The translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) to the nucleus and the molecular docking suggested that Andr might exert a therapeutic effect by influencing the Keap1-Nrf2 complex. In conclusions, this study revealed that Andr is a potential preventive therapeutic drug toward AF via activating the translocation of Nrf2 to the nucleus and the upregulation of heme oxygenase-1 (HO-1) to promote mitochondrial bioenergetics.
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Fibrilación Atrial , Animales , Conejos , Fibrilación Atrial/tratamiento farmacológico , Fibrilación Atrial/prevención & control , Fibrilación Atrial/metabolismo , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Transducción de Señal , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/farmacología , Simulación del Acoplamiento Molecular , Estrés Oxidativo , Metabolismo Energético , Mitocondrias/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Hemo-Oxigenasa 1RESUMEN
Congenital cataract is the commonest cause of visual impairment and blindness in children worldwide. Among congenital cataract cases, ~25% are caused by genetic defects, while several genetic mutations have been identified in hereditary cataract. In the present study, a patient with cataract underwent clinical ophthalmic examination and pedigree analysis. Whole exome sequencing and Sanger sequencing were performed to identify and verify gene mutations. The frequency, conservation, pathogenicity and hydrophobicity of the mutated amino acids were analyzed by bioinformatics analysis. The clinical examination and investigation verified that the probands of family A and C suffered from nuclear cataracts. In addition, the proband of family B was diagnosed with white punctate opacity. The pattern of inheritance was autosomal dominant. The sequencing analysis results revealed a mutation c.592-c593insG (p.W198Wfs*22) in exon 6 of CRYBA1/A3, a known mutation c.463C > T (p.Q155X) in exon 6 of CRYBB2 and a third mutation c.865c.866insC (p.T289Tfs*91) in exon 2 of GJA8. Each variant was cosegregated with disease in family And the mutation frequency in the database was <0.01. It has been reported that the mutation sites are highly conserved among different species, thus greatly affecting the sequence and structure of a protein, while exhibiting high pathogenicity in theory. The two crystallin gene mutations could notably enhance the local hydrophobicity of the protein, eventually resulting in its reduced solubility and destruction of lens transparency. The current study identified pathogenic genes in three families with congenital cataract and analyzed the association between mutation sites and different cataract phenotypes. Overall, the results could expand the genotype spectrum of congenital cataract and provide evidence for its clinical diagnosis.
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Catarata , Humanos , Secuenciación del Exoma , Linaje , Mutación , Catarata/diagnóstico , Catarata/genética , Catarata/congénito , Biología Molecular , Análisis Mutacional de ADNRESUMEN
Bacterial infection has been considered as a significant obstacle for wound healing. Nitric oxide (NO), as a novel alternative for antibiotics, has emerged as a promising antibacterial agent. However, the precise spatiotemporal controlled release of NO still remains a major challenge. Herein, a near-infrared (NIR) light triggered NO release nanoplatform (designated as PB-NO@PDA-PHMB) with enhanced broad-spectrum antibacterial and anti-biofilm properties was constructed. Given that PB-NO@PDA-PHMB has strong absorption in the NIR region and exhibits excellent photothermal effect, it can rapidly trigger NO release by NIR irradiation. PB-NO@PDA-PHMB can effectively contact and capture bacteria, and then exhibit synergistic effect of photothermal and gas therapy. In vitro and in vivo experiments indicated that PB-NO@PDA-PHMB exhibited excellent biocompatibility, satisfactory synergistic antibacterial efficacy and the capability of accelerating wound healing. Under NIR irradiation (808 nm, 1 W cm-2, 7 min), PB-NO@PDA-PHMB (80 µg mL-1) achieved 100% bactericidal activity against both Gram-negative bacteria Escherichia coli (E. coli) and Gram-positive bacteria Staphyloccocus aureus (S. aureus), removed 58.94% of S. aureus biofilm. Therefore, this all-in-one antibacterial nanoplatform with high NIR responsiveness provides a promising antibiotic-free strategy for bacterial infection treatment.
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Infecciones Bacterianas , Óxido Nítrico , Humanos , Escherichia coli , Staphylococcus aureus , Antibacterianos/farmacologíaRESUMEN
Bacterial biofilm seriously impedes the healing of infected wound, remaining a major challenge in wound repair. Antibiotic-free antibacterial strategies based on nanotechnology are emerging as promising tools to combat bacterial infections. Here, halloysite nanotube (HNT), as a natural clay mineral, was employed to fabricate a multifunctional platform (designated as HNTs@CuS@PDA-Lys) through a layer-by-layer strategy for treating bacterial infections by utilizing synergistic lysozyme (Lys)-photothermal therapy (PTT). Specifically, amino-modified HNTs were first decorated with copper sulfide (CuS), followed by coated with a polydopamine (PDA) layer, then functionalized with antimicrobial enzyme Lys onto the surface of PDA via cation-π interactions. The as-prepared HNTs@CuS@PDA-Lys at a low dose (200 µg/mL) exhibited excellent synergistic Lys-photothermal bactericidal activity against Escherichia coli (E. coli) (100.0 ± 0.2 %) and Staphyloccocus aureus (S. aureus) (99.9 ± 0.1 %), eliminated 75.9 ± 2.0 % of S. aureus biofilm under near-infrared (NIR) irradiation (808 nm, 1.5 W/cm2). In vivo experiments using a S. aureus-infected rat model showed HNTs@CuS@PDA-Lys could rapidly kill bacteria and accelerate wound healing process. Overall, this multifunctional nanoplatform combines the advantages of PTT and Lys, providing a cost-efficient, environmental friendly strategy for bacterial and biofilm eradication, demonstrating the potential applications in the field of biomedicine.
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Escherichia coli , Nanotubos , Ratas , Animales , Arcilla , Terapia Fototérmica , Staphylococcus aureus , Muramidasa/farmacología , Hidrólisis , Antibacterianos/farmacología , CatálisisRESUMEN
Ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) is a unique component of the ubiquitin-proteasome system (UPS), which has multiple activities in maintaining intracellular ubiquitin levels. We previously reported the aberrant low expression of UCHL1 in podocytes of non-immune complex-mediated glomerulonephritis, and recent studies indicate that anti-UCHL1 antibody was responsible for the refractory minimal change disease (MCD), but the specific effect of UCHL1 to the podocytopathy has not been determined. Therefore, we generated podocyte-specific UCHL1 gene knockout (UCHL1cre/cre) rats model. Podocyte-specific UCHL1 knockout rats exhibited severe kidney damage, including segmental/global glomerulosclerosis, kidney function damage and severe proteinuria, compared with littermate control. Subsequently, by carrying out mass spectrometry analysis of isolated glomeruli of rats, abnormal protein accumulation of ECM-receptor Interaction was found in UCHL1cre/cre rats. Mechanistic studies in vivo and in vitro revealed that aberrant protein accumulation after UCHL1 deficiency induced endoplasmic reticulum (ER) stress, unfolded protein reaction (UPR) to reduce the protein level of podocyte skeleton proteins, and CHOP mediated apoptosis as well, which related to the dysfunction of the ubiquitin-proteasome system with decreased free monomeric ubiquitin level, thereby affecting protein ubiquitination and degradation. In addition, inhibition of ER stress by 4-PBA could attenuate the degree of ER stress and podocyte dysfunction. Our study indicates that UCHL1 is a potential target for preventing podocytes injury in some non-immune complex-mediated glomerulopathy.
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Enfermedades Renales , Podocitos , Ratas , Animales , Podocitos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , Estrés del Retículo Endoplásmico/genética , Enfermedades Renales/metabolismo , Ubiquitina Tiolesterasa/metabolismoRESUMEN
Cell cycle checkpoint kinases play a pivotal role in protecting against replicative stress. In this study, valproic acid (VPA), a histone deacetylase inhibitor (HDACi), was found to promote breast cancer MCF-7 cells to traverse into G2/M phase for catastrophic injury by promoting PPP2R2A (the B-regulatory subunit of Phosphatase PP2A) to facilitate the dephosphorylation of Chk1 at Ser317 and Ser345. By contrast, VPA protected normal 16HBE cells from HU toxicity through decreasing PPP2R2A expression and increasing Chk1 phosphorylation. The effect of VPA on PPP2R2A was at the post-transcription level through HDAC1/2. The in vitro results were affirmed in vivo. Patients with lower PPP2R2A expression and higher pChk1 expression showed significantly worse survival. PPP2R2A D197 and N181 are essential for PPP2R2A-Chk1 signaling and VPA-mediated bidirectional effect on augmenting HU-induced tumor cell death and protecting normal cells.
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Inhibidores de Histona Desacetilasas , Ácido Valproico , Humanos , Ácido Valproico/farmacología , División Celular , Fosforilación , Inhibidores de Histona Desacetilasas/farmacología , Replicación del ADN , Ciclo Celular , Línea Celular Tumoral , Proteína Fosfatasa 2/metabolismoRESUMEN
AIMS: The dedifferentiation of tubular epithelial cells has been identified as an important trigger of renal fibrosis. The Hippo pathway is a crucial regulator of cell proliferation and differentiation. In this study, we determined the role of Hippo proteins in tubular dedifferentiation in diabetic nephropathy (DN). MAIN METHODS: In this study, we measured dedifferentiation markers and Hippo proteins in db/db mice and high glucose treated tubular epithelial cells. Then, verteporfin and knockdown of large tumor suppressor kinase (LATS) 1 and 2 were performed to uncover therapeutic targets for DN. KEY FINDINGS: Here, we found dedifferentiation and upregulated Hippo proteins in tubular epithelial cells in DN model both in vivo and in vitro. Both verteporfin and LATS knockdown could inhibit the tubular mesenchymal transition, but verteporfin showed broad inhibitory effect on Hippo proteins, especially nuclear YAP, and exacerbated podocyte loss of DN. LATS2 knockdown did not reverse the tubular E-Cadherin loss while it also induced podocyte apoptosis. Overall, intervention of LATS1 inhibited tubular dedifferentiation efficiently without affecting YAP and bringing podocyte apoptosis. Further mechanistic investigations revealed that the TGF-ß1/Smad, instead of the YAP-TEAD-CTGF signaling, might be the underlying pathway through which verteporfin and LATS1 engaged in the tubular dedifferentiation. SIGNIFICANCE: In conclusion, verteporfin is not a suitable treatment for DN owing to evitable podocyte loss and apoptosis. Targeting LATS1 is a better choice worthy of further investigation for DN therapy.
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Diabetes Mellitus , Nefropatías Diabéticas , Podocitos , Animales , Ratones , Nefropatías Diabéticas/metabolismo , Podocitos/metabolismo , Proteínas Serina-Treonina Quinasas , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Verteporfina/farmacología , Verteporfina/uso terapéuticoRESUMEN
PURPOSE: The role of vacuolar protein sorting 34 (Vps34), an indispensable protein required for cell vesicular trafficking, in the biological behavior of hepatocellular carcinoma (HCC) has yet to be studied. MATERIALS AND METHODS: In the present study, the expression of Vps34 in HCC and the effect of Vps34 on HCC cell invasion was detected both in vivo and in vitro. Furthermore, by modulating the RILP and Rab11, which regulate juxtanuclear lysosome aggregation and recycling endosome respectively, the underlying mechanism was investigated. RESULTS: Vps34 was significantly decreased in HCC and negatively correlated with the HCC invasiveness both in vivo and in vitro. Moreover, Vps34 could promote lysosomal juxtanuclear accumulation, reduce the invasive ability of HCC cells via the Rab7-RILP pathway. In addition, the deficiency of Vps34 in HCC cells affected the endosome-lysosome system, resulting in enhanced Rab11 mediated endocytic recycling of cell surface receptor and increased invasion of HCC cells. CONCLUSION: Our study reveals that Vps34 acts as an invasion suppressor in HCC cells, and more importantly, the endosome-lysosome trafficking regulated by Vps34 has the potential to become a target pathway in HCC treatment.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Hepatocelular/metabolismo , Fosfatidilinositol 3-Quinasas Clase III/metabolismo , Neoplasias Hepáticas/metabolismo , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Desnudos , Invasividad Neoplásica , Proteínas de Unión a GTP rab7/metabolismoRESUMEN
Nod-like receptor protein 3 (NLRP3), as an inflammatory regulator, has been implicated in acute kidney injury (AKI). Failed recovery after AKI can lead to chronic kidney disease (CKD). However, the role of NLRP3 in the AKI-CKD transition is still unknown. A mild or severe AKI mouse model was performed by using ischemia-reperfusion injury (IRI). We evaluated the renal NLRP3 expression in acute and chronic phases of ischemic AKI, respectively. Although serum creatinine (Cr) and blood urea nitrogen (BUN) levels in AKI chronic phase were equivalent to normal baseline, histological analysis and fibrotic markers revealed that severe AKI-induced maladaptive tubular repair with immune cell infiltration and fibrosis. Tubular damage was restored completely in mild AKI rather than in severe AKI. Of note, persistent overexpression of NLRP3 was also found in severe AKI but not in mild AKI. In the severe AKI-induced chronic phase, there was a long-term high level of NLRP3 in serum or urine. Overt NLRP3 was mainly distributed in the abnormal tubules surrounded by inflammatory infiltrates and fibrosis, which indicated the maladaptive repair. Renal Nlrp3 overexpression was correlated with infiltrating macrophages and fibrosis. Renal NLRP3 signaling-associated genes were upregulated after severe AKI by RNA-sequencing. Furthermore, NLRP3 was found increased in renal tubular epitheliums from CKD biopsies. Together, persistent NLRP3 overexpression was associated with chronic pathological changes following AKI, which might be a new biomarker for evaluating the possibility of AKI-CKD transition.
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BACKGROUND: Previously, by using proteomic analysis and RNA sequencing in isolated glomeruli, we identified several novel differentially expressed proteins in human and mouse diabetic nephropathy (DN) versus controls, including dishevelled associated activator of morphogenesis 2 (DAAM2). DAAM2 binds the Wnt effector Dvl. We aimed to study possible contributions of DAAM2 to DN. METHODS: We assessed DAAM2 by immunostaining in non-cancer regions of human nephrectomy (Nx), DN and normal donor kidney tissues. We also examined DAAM2 in DN mice (db/db eNOS-/-) and Nx mice. DN mice treated with angiotensin-converting enzyme inhibitor (ACEI), dipeptidyl peptidase 4 inhibitor (DPP4I) or vehicle were compared. DAAM2 was knocked down in primary cultured podocytes by small interfering RNA to study its effects on cell function. RESULTS: In normal human glomeruli, DAAM2 was expressed only on podocytes. DAAM2 expression was increased in both Nx and DN versus normal donors. Podocyte DAAM2 expression was increased in DN and Nx mouse models. Glomerular DAAM2 expression correlated with glomerular size and was decreased significantly by ACEI while DPP4I only numerically reduced DAAM2. In primary cultured podocytes, knockdown of DAAM2 enhanced adhesion, slowed migration, activated Wnt-ß-catenin signaling and downregulated mammalian target of rapamycin complex 1 (mTORC1) and Rho activity. CONCLUSIONS: Podocyte DAAM2 is upregulated in both Nx and DN, which could be contributed to by glomerular hypertrophy. We hypothesize that DAAM2 regulates podocyte function through the mTORC1, Wnt/ß-catenin and Rho signaling pathways.
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Diabetes Mellitus , Nefropatías Diabéticas , Podocitos , Animales , Nefropatías Diabéticas/etiología , Glomérulos Renales , Ratones , Proteínas de Microfilamentos , Morfogénesis , Proteómica , Proteínas de Unión al GTP rhoRESUMEN
Tuberous sclerosis complex (TSC) is characterized by hamartomatous lesions in multiple organs, with most patients developing polycystic kidney disease and leading to a decline of renal function. TSC is caused by loss-of-function mutations in either Tsc1 or Tsc2 gene, but currently, there is no effective treatment for aberrant kidney growth in TSC patients. By generating a renal proximal tubule-specific Tsc1 gene-knockout (Tsc1 ptKO) mouse model, we observed that Tsc1 ptKO mice developed aberrantly enlarged kidneys primarily due to hypertrophy and proliferation of proximal tubule cells, along with some cystogenesis, interstitial inflammation, and fibrosis. Mechanistic studies revealed inhibition of AMP-activated protein kinase (AMPK) phosphorylation at Thr-172 and activation of Akt phosphorylation at Ser-473 and Thr-308. We therefore treated Tsc1 ptKO mice with the AMPK activator, metformin, by daily intraperitoneal injection. Our results indicated that metformin increased the AMPK phosphorylation, but decreased the Akt phosphorylation. These signaling modulations resulted in inhibition of proliferation and induction of apoptosis in the renal proximal tubule cells of Tsc1 ptKO mice. Importantly, metformin treatment effectively prevented aberrant kidney enlargement and cyst growth, inhibited inflammatory response, attenuated interstitial fibrosis, and protected renal function. The effects of metformin were further confirmed by in vitro experiments. In conclusion, this study indicates a potential therapeutic effect of metformin on Tsc1 deletion-induced kidney pathology, although currently metformin is primarily prescribed to treat patients with type 2 diabetes.
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UCH-L1 is a de-ubiquitination enzyme comprehensively distributed in neural cells and podocytes, which is involved in several kinds of nervous system and kidney related diseases. Our previous studies have demonstrated the aberrant up-regulation of UCH-L1 in podocytes of renal diseases, but how dose podocytes are injured by up-regulated UCH-L1 is waiting to be elucidated. Here, we observed the cytoskeleton rearrangement in podocytes with over-expression of UCH-L1, accompanied with a down-regulation of synaptopodin and RhoA, which are closely related to cytoskeletal stabilization. However, we did not see any alteration of RhoA ubiquitination level under the stimulation of UCH-L1 in podocytes. Subsequently, mass spectrum was applied in UCH-L1-flag immunoprecipitation and plakoglobin was screened out, which was among the UCH-L1-combined proteins and most likely related to cytoskeleton rearrangement. Our experiment demonstrates UCH-L1 may not injure podocytes cytoskeleton through a direct regulation on RhoA/Synaptopodin, but through the regulation of plakoglobin, which could be a promising target for treatment of renal disease in the future.
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Podocitos/metabolismo , Ubiquitina Tiolesterasa/metabolismo , Animales , Línea Celular , Citoesqueleto/metabolismo , Citoesqueleto/patología , Humanos , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Ratones , Proteínas de Microfilamentos/metabolismo , Podocitos/patología , Ubiquitinación , gamma Catenina/metabolismo , Proteína de Unión al GTP rhoA/metabolismoRESUMEN
Diabetic nephrology (DN) is attributed largely to the depletion of podocytes, which is closely associated to apoptosis. However, the complex mechanism of podocyte loss in DN pathogenesis remains unclear. Recently, necroptosis has emerged as an important cell death model in many pathological conditions, which is regulated through RIPK1/RIPK3 pathway. In addition, necroptosis was found to share several upstream signaling pathways with apoptosis. Therefore, it was speculated that both apoptosis and necroptosis may occur in podocytes during the process of podocyte injury in DN. Herein, necroptosis and apoptosis were shown to be involved in podocyte injury induced by high glucose (HG), both in vitro and in vivo, with a high level of positive signaling markers RIPK1 (298.4⯱â¯17.35), cleaved caspase 3 (497.1⯱â¯23.09), RIPK3 (108.4⯱â¯14.92), and MLKL (470.4⯱â¯15.73) than the control groups. Scaning electron microscopy examination revealed the morphological characteristics of necroptotic and apoptotic cells, which differed remarkably. z-VAD-fmk, a pan-inhibitor of apoptosis, could block apoptosis and enhance necroptosis. Furthermore, UCHL1 was found to play a major role in promoting podocyte necroptosis by regulating the ubiquitination state of the RIPK1/RIPK3 pathway. The half-life of RIPK1 and RIPK3 proteins reduced and the expression of RIPK1, RIPK3, and MLKL decreased significantly after the knockdown of UCHL1. It was shown that UCHL1 exerted a more regulatory response to necroptosis. These data suggested that necroptosis may have more effect on the loss of podocytes than apoptosis in DN with the regulation of UCHL1. Thus, inhibiting UCHL1 to downregulate the RIPK1/RIPK3 pathway may be a novel strategy to protect the podocytes in DN patients.
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Apoptosis/efectos de los fármacos , Glucosa/toxicidad , Necroptosis/efectos de los fármacos , Podocitos/patología , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Transducción de Señal , Ubiquitina Tiolesterasa/metabolismo , Adulto , Clorometilcetonas de Aminoácidos/farmacología , Caspasa 3/metabolismo , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Femenino , Humanos , Imidazoles/farmacología , Indoles/farmacología , Masculino , Persona de Mediana Edad , Podocitos/efectos de los fármacos , Podocitos/ultraestructura , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Quinasas/metabolismo , Proteolisis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ubiquitina/metabolismo , Ubiquitinación/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacosRESUMEN
OBJECTIVES: Acute kidney injury (AKI) is a growing global health concern, and is associated with high rates of mortality and morbidity in intensive care units. Se is a trace element with antioxidant properties. This study aimed to determine whether porous Se@SiO2 nanospheres could relieve oxidative stress and inflammation in ischemia/reperfusion (I/R)-induced AKI. METHODS: Male 6- to 8-week-old C57bl/6 mice were divided into four groups: sham + saline, sham + Se@SiO2, I/R + saline, and I/R + Se@SiO2. Mice in the I/R groups experienced 30 minutes of bilateral renal I/R to induce an AKI. Porous Se@SiO2 nanospheres (1 mg/kg) were intraperitoneally injected into mice in the I/R + Se@SiO2 group 2 hours before I/R, and the same dose was injected every 12 hours thereafter. Hypoxia/reoxygenation (H/R) was used to mimic I/R in vitro. PBS was used as a control treatment. Human kidney 2 cells were seeded into 12-well plates (5×105 cells/well) and divided into four groups: control + PBS group, control + Se@SiO2 group, H/R + PBS group, and H/R + Se@SiO2 group (n=3 wells). We then determined the expression levels of ROS, glutathione, inflammatory cytokines and proteins, fibrosis proteins, and carried out histological analysis upon kidney tissues. RESULTS: In vitro, intervention with porous Se@SiO2 nanospheres significantly reduced levels of ROS (P<0.05), inflammatory cytokines (P<0.05), and inflammation-associated proteins (P<0.05). In vivo, tubular damage, cell apoptosis, and interstitial inflammation during AKI were reduced significantly following treatment with porous Se@SiO2 nanospheres. Moreover, the occurrence of fibrosis and tubular atrophy after AKI was attenuated by porous Se@SiO2 nanospheres. CONCLUSION: Porous Se@SiO2 nanospheres exhibited a protective effect in I/R-induced AKI by resisting oxidative stress and inflammation. This suggests that porous Se@SiO2 nanospheres may represent a new therapeutic method for AKI.
Asunto(s)
Lesión Renal Aguda/prevención & control , Antioxidantes/administración & dosificación , Inflamación/prevención & control , Nanosferas/administración & dosificación , Estrés Oxidativo/efectos de los fármacos , Daño por Reperfusión/complicaciones , Selenio/administración & dosificación , Dióxido de Silicio/administración & dosificación , Lesión Renal Aguda/etiología , Lesión Renal Aguda/patología , Animales , Antioxidantes/química , Inflamación/etiología , Inflamación/patología , Pruebas de Función Renal , Masculino , Ratones , Ratones Endogámicos C57BL , Nanosferas/química , Selenio/química , Dióxido de Silicio/químicaRESUMEN
Diabetic nephropathy (DN) is a major cause of end-stage renal disease throughout the world in both developed and developing countries. This review briefly introduces the characteristic pathological changes of DN and Tervaert pathological classification, which divides DN into four classifications according to glomerular lesions, along with a separate scoring system for tubular, interstitial, and vascular lesions. Given the heterogeneity of the renal lesions and the complex mechanism underlying diabetic nephropathy, Tervaert classification has both significance and controversies in the guidance of diagnosis and prognosis. Applications and evaluations using Tervaert classification and indications for renal biopsy are summarized in this review according to recent studies. Meanwhile, differential diagnosis with another nodular glomerulopathy and the situation that a typical DN superimposed with a nondiabetic renal disease (NDRD) are discussed and concluded in this review.
Asunto(s)
Nefropatías Diabéticas/clasificación , Nefropatías Diabéticas/diagnóstico , Enfermedades Renales/diagnóstico , Nefropatías Diabéticas/patología , Diagnóstico Diferencial , Humanos , Enfermedades Renales/patologíaRESUMEN
BACKGROUND: Studies concerning proteins are always a crucial part of renal research. As a result of current technologies, scientists have mastered several techniques for generating genetically modified animals. However, in most cases, accessing these animals is still time-consuming and often expensive. This makes the alteration of protein expression by in vivo plasmid transfection an easily-accessible alternative. However, there is still no comprehensive study describing where plasmids would be expressed when they are injected into the kidneys. METHODS: We injected pEGFP-N1 into rats via intra-/inter-renal channels and detected green fluorescent protein (GFP) by immunohistochemistry and immunofluorescence to localize plasmid expression. RESULTS: Seven days post-injection, we found that GFP was expressed in the glomeruli when pEGFP-N1 was injected via the renal artery or vein enhanced by electroporation and in the interstitium following injection via the ureter. Other channels, including intraperitoneal, subcapsule and parenchymal injection, only led to scattered expression within the kidneys. CONCLUSIONS: The present study provides evidence that plasmid transfection via the renal vessels is suitable for glomeruli research and that transfection via the ureter is appropriate for studies regarding interstitium lesions. Additionally, we provide evidence that plasmid transfection on live animals is still an applicable and useful tool, as well as being cost-effective and facile.